杨丽梅, 印传磊, 马庆丰, et al. Production Practice of 90 t BOF⁃RH⁃CC Process for ZG⁃12 Ultra⁃low Phosphorus Steel[J]. Special Steel, 2023, 44(1): 15-18. DOI: 10.20057/j.1003-8620.2022-00035.
In the light of problems of smelting ultra-low phosphorus steel (%/: <0. 03C、<0. 01 OP、<0. 015S、< 0.06Mn、vO. 02Cr、<0.02Ni)
the lower liquid temperature at 90 t BOF tapping and serious overoxidation of liquid
led to heating refining by LF
are tested and studied by process optimization. The results show that during BOF (0. 018% - 0. 025% P) tapping process by adding lime and refining slag to produce slag with binary alkalinity 7 and P2O5 <0.5%
the dephosphorization rate of liquid in ladle reaches up to 75%
the phosphorus content of finished products is less than 0.010%
the smelting time is shortened by 3 ~ 4 min. At the same time
the dephosphorization rate of ladle decreases with the increase of liquid steel temperature at the end of converter blowing
the BOF optimum end-point temperature is between 1 630 °C and 1 655 °C. By adopting ladle dephosphorization technology
the smelting process of ultra-low phosphorus steel is shortened to converter blowing—►RH treatment—►continuous casting